diff --git a/lib/header.c b/lib/header.c
index 46bdb032..036abe0d 100644
--- a/lib/header.c
+++ b/lib/header.c
@@ -143,16 +143,17 @@ STORE_IN_ROM static const char * const err500[] = {
 };
 
 int
-lws_add_http_header_status(struct lws *wsi, unsigned int code,
+lws_add_http_header_status(struct lws *wsi, unsigned int _code,
 			   unsigned char **p, unsigned char *end)
 {
-	const struct lws_protocol_vhost_options *headers;
-	unsigned char code_and_desc[60];
-	const char *description = "", *p1;
-	int n;
 	STORE_IN_ROM static const char * const hver[] = {
 		"HTTP/1.0", "HTTP/1.1", "HTTP/2"
 	};
+	const struct lws_protocol_vhost_options *headers;
+	unsigned int code = _code & LWSAHH_CODE_MASK;
+	const char *description = "", *p1;
+	unsigned char code_and_desc[60];
+	int n;
 
 #ifdef LWS_WITH_ACCESS_LOG
 	wsi->access_log.response = code;
@@ -181,11 +182,9 @@ lws_add_http_header_status(struct lws *wsi, unsigned int code,
 	else
 		p1 = hver[0];
 
-	n = sprintf((char *)code_and_desc, "%s %u %s",
-		    p1, code, description);
+	n = sprintf((char *)code_and_desc, "%s %u %s", p1, code, description);
 
-	if (lws_add_http_header_by_name(wsi, NULL, code_and_desc,
-					   n, p, end))
+	if (lws_add_http_header_by_name(wsi, NULL, code_and_desc, n, p, end))
 		return 1;
 
 	headers = wsi->vhost->headers;
@@ -199,13 +198,11 @@ lws_add_http_header_status(struct lws *wsi, unsigned int code,
 		headers = headers->next;
 	}
 
-	if (wsi->context->server_string)
-		if (lws_add_http_header_by_token(wsi,
-					 WSI_TOKEN_HTTP_SERVER,
-					 (unsigned char *)
-					 	 wsi->context->server_string,
-					 wsi->context->server_string_len,
-					 p, end))
+	if (wsi->context->server_string &&
+	    !(_code & LWSAHH_FLAG_NO_SERVER_NAME))
+		if (lws_add_http_header_by_token(wsi, WSI_TOKEN_HTTP_SERVER,
+				(unsigned char *)wsi->context->server_string,
+				wsi->context->server_string_len, p, end))
 			return 1;
 
 	if (wsi->vhost->options & LWS_SERVER_OPTION_STS)
diff --git a/lib/libwebsockets.h b/lib/libwebsockets.h
index d76a5580..ffdcc842 100644
--- a/lib/libwebsockets.h
+++ b/lib/libwebsockets.h
@@ -2589,6 +2589,7 @@ enum http_status {
 	HTTP_STATUS_MOVED_PERMANENTLY				= 301,
 	HTTP_STATUS_FOUND					= 302,
 	HTTP_STATUS_SEE_OTHER					= 303,
+	HTTP_STATUS_NOT_MODIFIED				= 304,
 
 	HTTP_STATUS_BAD_REQUEST					= 400,
 	HTTP_STATUS_UNAUTHORIZED,
@@ -2909,6 +2910,10 @@ lws_get_urlarg_by_name(struct lws *wsi, const char *name, char *buf, int len);
  * and fail with nonzero return.
  */
 ///@{
+
+#define LWSAHH_CODE_MASK			((1 << 16) - 1)
+#define LWSAHH_FLAG_NO_SERVER_NAME		(1 << 30)
+
 /**
  * lws_add_http_header_status() - add the HTTP response status code
  *
@@ -2917,7 +2922,11 @@ lws_get_urlarg_by_name(struct lws *wsi, const char *name, char *buf, int len);
  * \param p: pointer to current position in buffer pointer
  * \param end: pointer to end of buffer
  *
- * Adds the initial response code, so should be called first
+ * Adds the initial response code, so should be called first.
+ *
+ * Code may additionally take OR'd flags:
+ *
+ *    LWSAHH_FLAG_NO_SERVER_NAME:  don't apply server name header this time
  */
 LWS_VISIBLE LWS_EXTERN int LWS_WARN_UNUSED_RESULT
 lws_add_http_header_status(struct lws *wsi,
diff --git a/lib/server.c b/lib/server.c
index 94eb0d0a..26884d88 100644
--- a/lib/server.c
+++ b/lib/server.c
@@ -445,7 +445,8 @@ lws_http_serve(struct lws *wsi, char *uri, const char *origin,
 				   uri, origin);
 
 			/* we don't need to send the payload */
-			if (lws_add_http_header_status(wsi, 304, &p, end))
+			if (lws_add_http_header_status(wsi,
+					HTTP_STATUS_NOT_MODIFIED, &p, end))
 				return -1;
 
 			if (lws_add_http_header_by_token(wsi,
@@ -1066,7 +1067,7 @@ lws_http_action(struct lws *wsi)
 		p = buffer + LWS_PRE;
 		end = p + sizeof(buffer) - LWS_PRE;
 
-		if (lws_add_http_header_status(wsi, 200, &p, end))
+		if (lws_add_http_header_status(wsi, HTTP_STATUS_OK, &p, end))
 			return 1;
 		if (lws_add_http_header_by_token(wsi, WSI_TOKEN_CONNECTION,
 				(unsigned char *)"close", 5, &p, end))
diff --git a/plugins/generic-sessions/handlers.c b/plugins/generic-sessions/handlers.c
index f450a193..90276e5a 100644
--- a/plugins/generic-sessions/handlers.c
+++ b/plugins/generic-sessions/handlers.c
@@ -243,7 +243,7 @@ reply:
 	start = p;
 	end = p + sizeof(buffer) - LWS_PRE;
 
-	if (lws_add_http_header_status(wsi, 200, &p, end))
+	if (lws_add_http_header_status(wsi, HTTP_STATUS_OK, &p, end))
 		return -1;
 	if (lws_add_http_header_by_token(wsi, WSI_TOKEN_HTTP_CONTENT_TYPE,
 					 (unsigned char *)"text/plain", 10,
diff --git a/plugins/generic-sessions/protocol_lws_messageboard.c b/plugins/generic-sessions/protocol_lws_messageboard.c
index 4b2275c7..8cb2d77b 100644
--- a/plugins/generic-sessions/protocol_lws_messageboard.c
+++ b/plugins/generic-sessions/protocol_lws_messageboard.c
@@ -319,7 +319,7 @@ callback_messageboard(struct lws *wsi, enum lws_callback_reasons reason,
 		start = p;
 		end = p + sizeof(buffer) - LWS_PRE;
 
-		if (lws_add_http_header_status(wsi, 200, &p, end))
+		if (lws_add_http_header_status(wsi, HTTP_STATUS_OK, &p, end))
 			return -1;
 		if (lws_add_http_header_by_token(wsi, WSI_TOKEN_HTTP_CONTENT_TYPE,
 				(unsigned char *)"text/plain", 10, &p, end))
diff --git a/plugins/protocol_post_demo.c b/plugins/protocol_post_demo.c
index 18b6b602..bd9bef65 100644
--- a/plugins/protocol_post_demo.c
+++ b/plugins/protocol_post_demo.c
@@ -165,7 +165,7 @@ callback_post_demo(struct lws *wsi, enum lws_callback_reasons reason,
 		start = p;
 		end = p + n - LWS_PRE - 1;
 
-		if (lws_add_http_header_status(wsi, 200, &p, end))
+		if (lws_add_http_header_status(wsi, HTTP_STATUS_OK, &p, end))
 			goto bail;
 
 		if (lws_add_http_header_by_token(wsi, WSI_TOKEN_HTTP_CONTENT_TYPE,
diff --git a/test-server/test-server-http.c b/test-server/test-server-http.c
index 3b3029d8..81445ca7 100644
--- a/test-server/test-server-http.c
+++ b/test-server/test-server-http.c
@@ -311,7 +311,7 @@ int callback_http(struct lws *wsi, enum lws_callback_reasons reason, void *user,
 			 * depending on what connection it happens to be working
 			 * on
 			 */
-			if (lws_add_http_header_status(wsi, 200, &p, end))
+			if (lws_add_http_header_status(wsi, HTTP_STATUS_OK, &p, end))
 				return 1;
 			if (lws_add_http_header_by_token(wsi, WSI_TOKEN_HTTP_SERVER,
 				    	(unsigned char *)"libwebsockets",
@@ -473,7 +473,7 @@ int callback_http(struct lws *wsi, enum lws_callback_reasons reason, void *user,
 		start = p;
 		end = p + sizeof(buffer) - LWS_PRE;
 
-		if (lws_add_http_header_status(wsi, 200, &p, end))
+		if (lws_add_http_header_status(wsi, HTTP_STATUS_OK, &p, end))
 			return 1;
 
 		if (lws_add_http_header_by_token(wsi, WSI_TOKEN_HTTP_CONTENT_TYPE,
@@ -615,7 +615,7 @@ bail:
 		lwsl_err("LWS_CALLBACK_ESTABLISHED_CLIENT_HTTP\n");
 		p = buffer + LWS_PRE;
 		end = p + sizeof(buffer) - LWS_PRE;
-		if (lws_add_http_header_status(lws_get_parent(wsi), 200, &p, end))
+		if (lws_add_http_header_status(lws_get_parent(wsi), HTTP_STATUS_OK, &p, end))
 			return 1;
 		if (lws_add_http_header_by_token(lws_get_parent(wsi),
 				WSI_TOKEN_HTTP_SERVER,